r. svoboda oct, 2008diwan/talks/udig/udig-svoboda.pdf · r/p hrs ~16% / day 3 injected pure water @...
TRANSCRIPT
![Page 1: R. Svoboda Oct, 2008diwan/talks/udig/UDIG-Svoboda.pdf · R/P Hrs ~16% / day 3 Injected Pure Water @ 8 MOhm Test of GdCl3 Addition at 400 nm Preliminary Injected Pure Water See W.Coleman,](https://reader033.vdocuments.site/reader033/viewer/2022051920/600cec62bcc6cb3aad501e50/html5/thumbnails/1.jpg)
R. SvobodaOct, 2008
![Page 2: R. Svoboda Oct, 2008diwan/talks/udig/UDIG-Svoboda.pdf · R/P Hrs ~16% / day 3 Injected Pure Water @ 8 MOhm Test of GdCl3 Addition at 400 nm Preliminary Injected Pure Water See W.Coleman,](https://reader033.vdocuments.site/reader033/viewer/2022051920/600cec62bcc6cb3aad501e50/html5/thumbnails/2.jpg)
Mature Detector Technology• IMB, Kamiokande, Super-K, SNO(D2O),
miniBooNE (oil)
• “Mature” = 3/5 did not have serious accident
• We know some of the major problems that can cause a disaster
• We know what to do to improve with little technical or schedule risk
![Page 3: R. Svoboda Oct, 2008diwan/talks/udig/UDIG-Svoboda.pdf · R/P Hrs ~16% / day 3 Injected Pure Water @ 8 MOhm Test of GdCl3 Addition at 400 nm Preliminary Injected Pure Water See W.Coleman,](https://reader033.vdocuments.site/reader033/viewer/2022051920/600cec62bcc6cb3aad501e50/html5/thumbnails/3.jpg)
Water Cerenkov Joins Ranks of Other Boring Detector Technologies!
• Liquid Scintillator (Nona, Daya Bay, Double Chooz, Borexino, KamLAND, LENA)
• Silicon Detectors (CDF, CMS, ATLAS, PHENIX,…)
• Plastic Scintillator/Absorber (MINOS, K2K, T2K, ATLAS, CMS)
• Drift Tubes (CMS
• RPC (CMS, BELLE, Daya Bay)
• …
![Page 4: R. Svoboda Oct, 2008diwan/talks/udig/UDIG-Svoboda.pdf · R/P Hrs ~16% / day 3 Injected Pure Water @ 8 MOhm Test of GdCl3 Addition at 400 nm Preliminary Injected Pure Water See W.Coleman,](https://reader033.vdocuments.site/reader033/viewer/2022051920/600cec62bcc6cb3aad501e50/html5/thumbnails/4.jpg)
How can we improve?
• Bring down cost
• improve sensitivity
• improve electronics
• improve PMT response
• ensure implosion hardness
• improved analysis and simulation
• new photosensors (more tentative)
![Page 5: R. Svoboda Oct, 2008diwan/talks/udig/UDIG-Svoboda.pdf · R/P Hrs ~16% / day 3 Injected Pure Water @ 8 MOhm Test of GdCl3 Addition at 400 nm Preliminary Injected Pure Water See W.Coleman,](https://reader033.vdocuments.site/reader033/viewer/2022051920/600cec62bcc6cb3aad501e50/html5/thumbnails/5.jpg)
Gadolinium Doping
• sensitivity to neutron capture via 8 MeV gamma cascade (see M.Vagins, NNN08)
• Relic Diffuse SN flux (see talk at this conference)
• neutron tagging for proton decay background
• neutron tagging for low energy QE selection
• Challenge: water transparency, material compatibility
![Page 6: R. Svoboda Oct, 2008diwan/talks/udig/UDIG-Svoboda.pdf · R/P Hrs ~16% / day 3 Injected Pure Water @ 8 MOhm Test of GdCl3 Addition at 400 nm Preliminary Injected Pure Water See W.Coleman,](https://reader033.vdocuments.site/reader033/viewer/2022051920/600cec62bcc6cb3aad501e50/html5/thumbnails/6.jpg)
(10-20) x SK : event rate
• Exposure 1.6 Mton x year
– e.g., 0.2 Mt for 8 years
– Threshold 11.3 MeV, 100% efficiency
SN1987A-motivated (conservative)
Model-motivated (generic)
Max. allowed by SK limit
~22-128 ~250 ...
C.L., Astropart.Phys.26:190-201,2006, Fogli et al. JCAP 0504:002,2005,
Volpe & Welzel, 2007, C.L. & O.L.G. Peres, to appear soon.
![Page 7: R. Svoboda Oct, 2008diwan/talks/udig/UDIG-Svoboda.pdf · R/P Hrs ~16% / day 3 Injected Pure Water @ 8 MOhm Test of GdCl3 Addition at 400 nm Preliminary Injected Pure Water See W.Coleman,](https://reader033.vdocuments.site/reader033/viewer/2022051920/600cec62bcc6cb3aad501e50/html5/thumbnails/7.jpg)
Potential Discovery for DUSEL
• Depends on stellar formation rate at z>0.5
• Test collapse models without waiting for galactic SN
C.L., Astropart.Phys.26:190-201,2006
C.Lunardini
![Page 8: R. Svoboda Oct, 2008diwan/talks/udig/UDIG-Svoboda.pdf · R/P Hrs ~16% / day 3 Injected Pure Water @ 8 MOhm Test of GdCl3 Addition at 400 nm Preliminary Injected Pure Water See W.Coleman,](https://reader033.vdocuments.site/reader033/viewer/2022051920/600cec62bcc6cb3aad501e50/html5/thumbnails/8.jpg)
![Page 9: R. Svoboda Oct, 2008diwan/talks/udig/UDIG-Svoboda.pdf · R/P Hrs ~16% / day 3 Injected Pure Water @ 8 MOhm Test of GdCl3 Addition at 400 nm Preliminary Injected Pure Water See W.Coleman,](https://reader033.vdocuments.site/reader033/viewer/2022051920/600cec62bcc6cb3aad501e50/html5/thumbnails/9.jpg)
![Page 10: R. Svoboda Oct, 2008diwan/talks/udig/UDIG-Svoboda.pdf · R/P Hrs ~16% / day 3 Injected Pure Water @ 8 MOhm Test of GdCl3 Addition at 400 nm Preliminary Injected Pure Water See W.Coleman,](https://reader033.vdocuments.site/reader033/viewer/2022051920/600cec62bcc6cb3aad501e50/html5/thumbnails/10.jpg)
![Page 11: R. Svoboda Oct, 2008diwan/talks/udig/UDIG-Svoboda.pdf · R/P Hrs ~16% / day 3 Injected Pure Water @ 8 MOhm Test of GdCl3 Addition at 400 nm Preliminary Injected Pure Water See W.Coleman,](https://reader033.vdocuments.site/reader033/viewer/2022051920/600cec62bcc6cb3aad501e50/html5/thumbnails/11.jpg)
![Page 12: R. Svoboda Oct, 2008diwan/talks/udig/UDIG-Svoboda.pdf · R/P Hrs ~16% / day 3 Injected Pure Water @ 8 MOhm Test of GdCl3 Addition at 400 nm Preliminary Injected Pure Water See W.Coleman,](https://reader033.vdocuments.site/reader033/viewer/2022051920/600cec62bcc6cb3aad501e50/html5/thumbnails/12.jpg)
![Page 13: R. Svoboda Oct, 2008diwan/talks/udig/UDIG-Svoboda.pdf · R/P Hrs ~16% / day 3 Injected Pure Water @ 8 MOhm Test of GdCl3 Addition at 400 nm Preliminary Injected Pure Water See W.Coleman,](https://reader033.vdocuments.site/reader033/viewer/2022051920/600cec62bcc6cb3aad501e50/html5/thumbnails/13.jpg)
Testing of Material Compatibility at LLNL/UC Davis
13
![Page 14: R. Svoboda Oct, 2008diwan/talks/udig/UDIG-Svoboda.pdf · R/P Hrs ~16% / day 3 Injected Pure Water @ 8 MOhm Test of GdCl3 Addition at 400 nm Preliminary Injected Pure Water See W.Coleman,](https://reader033.vdocuments.site/reader033/viewer/2022051920/600cec62bcc6cb3aad501e50/html5/thumbnails/14.jpg)
Injection andMeasurement
Optics
Storagetank
PMT tankDeionizingFiltering
Sterilization
Alignmentmirror
Nitrogen purge and relief valve
Nitrogen purge
Recirculationpump
drainmixing tankand pump
Light transmission arm
Baffled joints
14
![Page 15: R. Svoboda Oct, 2008diwan/talks/udig/UDIG-Svoboda.pdf · R/P Hrs ~16% / day 3 Injected Pure Water @ 8 MOhm Test of GdCl3 Addition at 400 nm Preliminary Injected Pure Water See W.Coleman,](https://reader033.vdocuments.site/reader033/viewer/2022051920/600cec62bcc6cb3aad501e50/html5/thumbnails/15.jpg)
Light
transmission
arm
Acrylic
window
reflected
beam
integrator primary
beam
integrator
beam splitter
PMT
PMT light
integrator
Lawrence Livermore National Laboratory
9.54 meters
Not shown: collamators, baffles, filters
LLNL Test Set-Up
15
337 N2 Laser
w/ dye attachement
![Page 16: R. Svoboda Oct, 2008diwan/talks/udig/UDIG-Svoboda.pdf · R/P Hrs ~16% / day 3 Injected Pure Water @ 8 MOhm Test of GdCl3 Addition at 400 nm Preliminary Injected Pure Water See W.Coleman,](https://reader033.vdocuments.site/reader033/viewer/2022051920/600cec62bcc6cb3aad501e50/html5/thumbnails/16.jpg)
0.650
0.670
0.690
0.710
0.730
0.750
0.770
0.790
0.0 50.0 100.0 150.0 200.0 250.0 300.0 350.0 400.0
Hrs
R/P
Sto
pp
ed
re
circ
+/- 2%
pure water fall off
in transparency over
time (337 nm)
0.9 %/day
Preliminary
Stability of Pure Water
![Page 17: R. Svoboda Oct, 2008diwan/talks/udig/UDIG-Svoboda.pdf · R/P Hrs ~16% / day 3 Injected Pure Water @ 8 MOhm Test of GdCl3 Addition at 400 nm Preliminary Injected Pure Water See W.Coleman,](https://reader033.vdocuments.site/reader033/viewer/2022051920/600cec62bcc6cb3aad501e50/html5/thumbnails/17.jpg)
0.04
0.05
0.06
0.07
0.08
0.09
0.1
0.11
0.12
10 60 110 160 210 260 310
R/P
Hrs
~16% / dayA
dd
ed 0
.2%
Gd
Cl3
Injected Pure Water
@ 8 MOhm
Test of GdCl3
Addition at 400 nm
Preliminary
Injected Pure Water
@13 MOhmSee W.Coleman, et al NIM A
Similar results at 337, 420 nm
![Page 18: R. Svoboda Oct, 2008diwan/talks/udig/UDIG-Svoboda.pdf · R/P Hrs ~16% / day 3 Injected Pure Water @ 8 MOhm Test of GdCl3 Addition at 400 nm Preliminary Injected Pure Water See W.Coleman,](https://reader033.vdocuments.site/reader033/viewer/2022051920/600cec62bcc6cb3aad501e50/html5/thumbnails/18.jpg)
Basic problem traced to stainless steel: Test with FeCl3
• 10 ppm Fe+3 ion makes water look like ice tea. Clearly very low levels can affect transparency
• 7 ppb Fe+3 reduced transparency by ~30%
• Conclusion: Problem with Super-K is very likely due to reaction of Cl ions with the stainless steel tank to produce very low levels of Fe ions in water
• Solution: Don’t use steel components!
![Page 19: R. Svoboda Oct, 2008diwan/talks/udig/UDIG-Svoboda.pdf · R/P Hrs ~16% / day 3 Injected Pure Water @ 8 MOhm Test of GdCl3 Addition at 400 nm Preliminary Injected Pure Water See W.Coleman,](https://reader033.vdocuments.site/reader033/viewer/2022051920/600cec62bcc6cb3aad501e50/html5/thumbnails/19.jpg)
Currently Funded R&D LLNL: What makes good water go bad?
- Super-Kamiokande water must be continuously
and cleaned – else transparency drops slowly
- Similar behavior seen in IMB (plastic walls)
and SNO (acrylic walls – but much slower degradation)
REDUCING THE REQUIREMENT FOR RECIRC WILL
LOWER COST OF MEGATON SCALE DETETOR, EVEN
IF NO GD ADDED
![Page 20: R. Svoboda Oct, 2008diwan/talks/udig/UDIG-Svoboda.pdf · R/P Hrs ~16% / day 3 Injected Pure Water @ 8 MOhm Test of GdCl3 Addition at 400 nm Preliminary Injected Pure Water See W.Coleman,](https://reader033.vdocuments.site/reader033/viewer/2022051920/600cec62bcc6cb3aad501e50/html5/thumbnails/20.jpg)
Current LLNL R&D Program(PI: S.Dazeley)
• Systematic testing of materials in water and doped water over next two years
• Improve 9-meter photometer sensitivity, stability
• Goal #1: certify materials to be used in tank liners, PMT mounting, etc.
• Goal #2: verify material compatibility for Gddoping by working with UCI/IPMU group
• Help in this project needed. Student support available.
![Page 21: R. Svoboda Oct, 2008diwan/talks/udig/UDIG-Svoboda.pdf · R/P Hrs ~16% / day 3 Injected Pure Water @ 8 MOhm Test of GdCl3 Addition at 400 nm Preliminary Injected Pure Water See W.Coleman,](https://reader033.vdocuments.site/reader033/viewer/2022051920/600cec62bcc6cb3aad501e50/html5/thumbnails/21.jpg)
![Page 22: R. Svoboda Oct, 2008diwan/talks/udig/UDIG-Svoboda.pdf · R/P Hrs ~16% / day 3 Injected Pure Water @ 8 MOhm Test of GdCl3 Addition at 400 nm Preliminary Injected Pure Water See W.Coleman,](https://reader033.vdocuments.site/reader033/viewer/2022051920/600cec62bcc6cb3aad501e50/html5/thumbnails/22.jpg)
![Page 23: R. Svoboda Oct, 2008diwan/talks/udig/UDIG-Svoboda.pdf · R/P Hrs ~16% / day 3 Injected Pure Water @ 8 MOhm Test of GdCl3 Addition at 400 nm Preliminary Injected Pure Water See W.Coleman,](https://reader033.vdocuments.site/reader033/viewer/2022051920/600cec62bcc6cb3aad501e50/html5/thumbnails/23.jpg)
![Page 24: R. Svoboda Oct, 2008diwan/talks/udig/UDIG-Svoboda.pdf · R/P Hrs ~16% / day 3 Injected Pure Water @ 8 MOhm Test of GdCl3 Addition at 400 nm Preliminary Injected Pure Water See W.Coleman,](https://reader033.vdocuments.site/reader033/viewer/2022051920/600cec62bcc6cb3aad501e50/html5/thumbnails/24.jpg)
![Page 25: R. Svoboda Oct, 2008diwan/talks/udig/UDIG-Svoboda.pdf · R/P Hrs ~16% / day 3 Injected Pure Water @ 8 MOhm Test of GdCl3 Addition at 400 nm Preliminary Injected Pure Water See W.Coleman,](https://reader033.vdocuments.site/reader033/viewer/2022051920/600cec62bcc6cb3aad501e50/html5/thumbnails/25.jpg)
Current/Future PMT R&D
• Working with Hamamatsu to improve PMT hardness
• improved QE will mean fewer PMTs needed for equivalent light collection
• Need to understand physics of implosion and improve PMT strength (new Wisconsin/RPI/BNL proposal to NSF)
• Future: needed to devise and unambiguously test anti-chain reaction
![Page 26: R. Svoboda Oct, 2008diwan/talks/udig/UDIG-Svoboda.pdf · R/P Hrs ~16% / day 3 Injected Pure Water @ 8 MOhm Test of GdCl3 Addition at 400 nm Preliminary Injected Pure Water See W.Coleman,](https://reader033.vdocuments.site/reader033/viewer/2022051920/600cec62bcc6cb3aad501e50/html5/thumbnails/26.jpg)
Electronics
• If we have 50,000 PMT’s and use same cabling scheme as used by SK, we need 13,000 km of cable!
• cross-talk, signal degradation, high cost associated with cable installation and storage
• how to improve this situation?
![Page 27: R. Svoboda Oct, 2008diwan/talks/udig/UDIG-Svoboda.pdf · R/P Hrs ~16% / day 3 Injected Pure Water @ 8 MOhm Test of GdCl3 Addition at 400 nm Preliminary Injected Pure Water See W.Coleman,](https://reader033.vdocuments.site/reader033/viewer/2022051920/600cec62bcc6cb3aad501e50/html5/thumbnails/27.jpg)
![Page 28: R. Svoboda Oct, 2008diwan/talks/udig/UDIG-Svoboda.pdf · R/P Hrs ~16% / day 3 Injected Pure Water @ 8 MOhm Test of GdCl3 Addition at 400 nm Preliminary Injected Pure Water See W.Coleman,](https://reader033.vdocuments.site/reader033/viewer/2022051920/600cec62bcc6cb3aad501e50/html5/thumbnails/28.jpg)
![Page 29: R. Svoboda Oct, 2008diwan/talks/udig/UDIG-Svoboda.pdf · R/P Hrs ~16% / day 3 Injected Pure Water @ 8 MOhm Test of GdCl3 Addition at 400 nm Preliminary Injected Pure Water See W.Coleman,](https://reader033.vdocuments.site/reader033/viewer/2022051920/600cec62bcc6cb3aad501e50/html5/thumbnails/29.jpg)
![Page 30: R. Svoboda Oct, 2008diwan/talks/udig/UDIG-Svoboda.pdf · R/P Hrs ~16% / day 3 Injected Pure Water @ 8 MOhm Test of GdCl3 Addition at 400 nm Preliminary Injected Pure Water See W.Coleman,](https://reader033.vdocuments.site/reader033/viewer/2022051920/600cec62bcc6cb3aad501e50/html5/thumbnails/30.jpg)
Boring things needed to make sure a One Billion Dollar Project is on the
Path to Assured Success• Detector Lining and PMT mounting
• Cavern costs and stability
• further work on an unambiguous guarantee of PMT stability
• further development of Gd doping and material compatibility
• other work: water soluble dyes (follow up on pioneering work by SNO), waveshifter plates (IMB)
![Page 31: R. Svoboda Oct, 2008diwan/talks/udig/UDIG-Svoboda.pdf · R/P Hrs ~16% / day 3 Injected Pure Water @ 8 MOhm Test of GdCl3 Addition at 400 nm Preliminary Injected Pure Water See W.Coleman,](https://reader033.vdocuments.site/reader033/viewer/2022051920/600cec62bcc6cb3aad501e50/html5/thumbnails/31.jpg)
• development of electronics that can be economically used in a megaton scale water detector
• DETECTOR SOFTWARE AND OPTIMIZATION
• coordination of world-wide effort (this is happening now)
![Page 32: R. Svoboda Oct, 2008diwan/talks/udig/UDIG-Svoboda.pdf · R/P Hrs ~16% / day 3 Injected Pure Water @ 8 MOhm Test of GdCl3 Addition at 400 nm Preliminary Injected Pure Water See W.Coleman,](https://reader033.vdocuments.site/reader033/viewer/2022051920/600cec62bcc6cb3aad501e50/html5/thumbnails/32.jpg)
The “Vision” thing
• Unprecedented Opportunity!
• A Shared Vision: Technology Choice
• What Will Get Us on The Road to Success?
• What Are Dangers on that Road?
• It Will be Tough
• Don’t Worry – Be Happy